A method of making a semiconductor chip package is characterized in that it utilizes a flexible film carrier (instead of conventional lead frame or substrate) to support a semiconductor chip during the assembly process. The method comprises the steps of: forming a plurality of through-holes in a flexible film carrier; laminating a metal layer on the lower surface of the flexible film carrier; etching the metal layer to form a plurality of connection pads corresponding to the through-holes; forming a metal coating on the surfaces of the connection pads which are not covered by the flexible film carrier; attaching a semiconductor chip to the upper surface of the flexible film carrier; electrically coupling bonding pads on the semiconductor chip to the connection pads; forming a package body over the upper surface of the flexible film carrier and the semiconductor chip.
Legal claims defining the scope of protection, as filed with the USPTO.
1. A method of making a semiconductor chip package comprising the steps of: providing a flexible film carrier having opposing upper and lower surfaces, the upper surface of the flexible film carrier having a die receiving area; forming a plurality of through-holes in the flexible film carrier, the through-holes being disposed around the die receiving area; laminating a metal layer on the lower surface of the flexible film carrier; etching the metal layer to form a plurality of connection pads having opposing front and backside surfaces, the front surface of each connection pad has a portion exposed within the corresponding through-hole; forming a metal coating on the surfaces of the connection pads which are not covered by the flexible film carrier; attaching a semiconductor chip to the die receiving area of the flexible film carrier, the semiconductor chip having a plurality of bonding pads; electrically coupling the bonding pads of the semiconductor chip to the front surfaces of the connection pads; forming a package body over the upper surface of the flexible film carrier and the semiconductor chip.
2. The method as claimed in claim 1, further comprising the step of printing solder paste on the backside surfaces of the connection pads exposed on the bottom of the package body.
3. The method as claimed in claim 1, wherein the metal layer is a copper foil.
4. The method as claimed in claim 1, wherein the metal coating comprises a layer of nickel covering the surfaces of the connection pads which are not covered by the flexible film carrier, and a layer of gold covering the nickel layer.
5. The method as claimed in claim 1, wherein the flexible film carrier is a resin film.
6. The method as claimed in claim 1, wherein the flexible film carrier is made of polyimide.
7. The method as claimed in claim 1, wherein the step of electrically coupling comprises a wire bonding the bonding pads of the semiconductor chip to the front surfaces of the connection pads.
Cooperative Patent Classification codes for this invention. Click any code to explore related patents in that topic.
November 19, 1999
August 7, 2001
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